Narrative:

Aircraft X was doing IFR practice approaches to runway 25. Aircraft Y wanted an IFR visual approach to runway 7. Per the local procedure; aircraft Y needed to be 7 NM from runway 7 until aircraft X was airborne and issued a turn away from the incoming traffic. Aircraft Y was 7NM from the runway 7 threshold when aircraft X was over the threshold. I didn't limit the tower to a low approach; and I didn't have any way to know when aircraft X was airborne because it had dropped off radar at the threshold (the radar site is right next to the runway about 1/3rd way down runway 25; so there is typically no radar coverage from the runway 25 threshold to 2/3 the way down the runway). Aircraft Y was 5 NM from runway 7 when aircraft X showed up at the departure end of runway 25 turning to heading 300. The 'airborne' requirement for opposite direction procedures is tricky for tower controllers to predict and not always obvious to the radar controller when an aircraft is airborne (which is the point the radar controller can allow the other aircraft past the cutoff point). I think it makes sense to add a mile to the cutoff points and changing the qualifier to the aircraft rolling. That way; when the radar controller receives the rolling call; they know it is okay to let the inbound aircraft past the cutoff point.

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Original NASA ASRS Text

Title: TOL TRACON Controller reported a loss of separation related to an opposite direction operation. The arrival and departure were not within the tolerance limits.

Narrative: Aircraft X was doing IFR practice approaches to Runway 25. Aircraft Y wanted an IFR Visual Approach to Runway 7. Per the local procedure; Aircraft Y needed to be 7 NM from Runway 7 until Aircraft X was airborne and issued a turn away from the incoming traffic. Aircraft Y was 7NM from the Runway 7 threshold when Aircraft X was over the threshold. I didn't limit the tower to a low approach; and I didn't have any way to know when Aircraft X was airborne because it had dropped off radar at the threshold (the radar site is right next to the runway about 1/3rd way down Runway 25; so there is typically no radar coverage from the Runway 25 threshold to 2/3 the way down the runway). Aircraft Y was 5 NM from Runway 7 when Aircraft X showed up at the departure end of Runway 25 turning to heading 300. The 'airborne' requirement for opposite direction procedures is tricky for tower controllers to predict and not always obvious to the radar controller when an aircraft is airborne (which is the point the radar controller can allow the other aircraft past the cutoff point). I think it makes sense to add a mile to the cutoff points and changing the qualifier to the aircraft rolling. That way; when the radar controller receives the rolling call; they know it is okay to let the inbound aircraft past the cutoff point.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.